The present invention relates to a system for adapting the Domain Name System (DNS), which has been used for mapping names to Internet Protocol (IP) addresses, to a broadcast environment, such as in a broadband cable or satellite television network. The invention enables the integration of Internet-type resources in the broadcast environment.
The DNS, as used in the environment of computer networks such as the Internet, is a tool for mapping domain names, which are short alphabetical names, to an IP address. For example, the domain name xe2x80x9cwww.gi.comxe2x80x9d may be mapped to an IP address such as xe2x80x9c196.0.5.93xe2x80x9d. The DNS provides a hierarchical domain-based naming scheme and a distributed database system for implementing the naming scheme.
In practice, an application program, such as a web browser, calls a library procedure known as a resolver, and passes the domain name to it. The resolver sends a data packet to a local DNS server, which looks up the name and returns the IP address to the resolver. The resolver provides the IP address to the application, which can use it to establish a connection with the computer represented by the domain name, such as a server.
A background discussion of the DNS can be found in A. Tanenbaum, Computer Networks, 3 rd ed., Prentice Hall PTR, 1996, pages 622-630.
However, with the-present desire to integrate Internet-type resources in the broadcast environment, it would be desirable to provide a system for resolving domain names in the broadcast environment. In particular, there is a need to provide a system that implements a broadcast domain space providing domain names for television resources, such as television programs, audio services, and Internet-type resources, such as web pages.
A system is needed that allows a server, or a set of servers, to specify the location of content and services within a broadcast using the domain name syntax. In addition, the system should allow client applications, such as a web browser, to locate any information that is part of a broadcast through the means of a domain name. Further, the system should allow defined broadcast domain names to be used within a Uniform Resource Locator (URL) to specify the location of broadcast content and services.
The system should be suitable for use in a digital video environment. Additionally, the system should be suitable for use with virtually any type of broadcast or interactive network, including a satellite network and a cable television network.
The system should organize the domain names in a domain name space, and provide information to network users in the form of a broadcast DNS message having a broadcast resource record that identifies a data source that is associated with a respective domain, where the data source can be a broadcast programming service, such as TV program, or other data, for example.
The broadcast resource records should be provided to the users in a non-interactive manner though periodic transmissions, or in an interactive manner, in response to a resolver query to a name server.
The system should allow different servers to manage different portions or zones of the domain name space.
The present invention provides a system having the above and other advantages.
The present invention relates to a system for adapting the Domain Name System (DNS), which has been used for mapping names to Internet Protocol (IP) addresses, to a broadcast environment, such as in a broadband cable or satellite television network.
A method for providing a broadcast domain name system includes the step of providing at least one master file at a broadcast domain name server to define at least one node within a broadcast domain name space. The node is provided in an associated zone of, and corresponds to, a domain within the broadcast domain name space, and the domain has an associated domain name. The master file is used to form a broadcast resource record that designates at least one attribute of the node. Subsequently, a message comprising the broadcast resource record is transmitted from the broadcast domain name server to a resolver to enable a user of the broadcast domain name system to resolve the domain name.
The domain name space may include a television-related domain, with sub-domains for different service providers (e.g., ABC, HBO), and a cable domain, with sub-domains for applications, administrative functions and operating system functions, e.g., at a set-top terminal. The television sub-domains may have their own sub-domains. For example, xe2x80x9cABCxe2x80x9d may have the sub-domains xe2x80x9cNEWSxe2x80x9d, xe2x80x9cWEATHERxe2x80x9d, xe2x80x9cSPORTSxe2x80x9d and so forth. The master files include broadcast resource records (BRRs) that identify the broadcast programming sources (e.g., xe2x80x9cABCxe2x80x9d).
When a query for a broadcast domain name is received from a-user program, e.g., from a user application of the set-top box, the corresponding BRR information is returned to the user program via a client resolver function. The corresponding BRR information identifies, e.g., an Internet Protocol address, a name, or a virtual channel that are associated with a data source that contains a service, e.g., a broadcast video programming service. Specifically, the BRRs are carried in a broadcast DNS message that is transmitted to a client resolver that a user program can access.
The broadcast resource records may be provided to a client resolver in a non-interactive manner, such as by periodic transmissions (e.g., carouseling, or some other predetermined scheduling) of the BDNS messages.
Alternatively, the broadcast resource records may be provided to a client resolver in a interactive manner, such as occurs with traditional DNS resource records.
A corresponding method for use at a resolver is also presented.
Corresponding apparatuses are also presented.